The present disclosure relates generally to a method and apparatus for providing positive contact force in an electrical contact assembly, and particularly to an electrical contact assembly having an Electronic Module (EM), such as a Single-Chip Module (SCM) or a Multi-Chip Module (MCM) for example, that may have a non-planar back that electrically mates with a Printed Circuit Board (PCB).
The continuous development in the electronics and computer industry has resulted in larger Electronic Modules (such as Multi-Chip Modules) being packaged in smaller spatial environments. Coupled with this density increase is a need to connect an increased number of processing module input/output terminals to PCBs. One device for interconnecting a high number of input/output terminals on a processing module to a PCB is a Land Grid Array (LGA) interconnect. Typically, a LGA interconnect is sandwiched between the processing module and the PCB to provide electrical connection between the terminals on the processing module and interconnects (such as pads and plated vias for example) on the PCB.
Some designs use clamping techniques to apply force to the processing module to maintain electrical contact between the processing module, the LGA interconnect and the PCB. However, the bottom mating surface of the EM and the top surface of the PCB may be non-planar, with a surface camber that may vary significantly, such as about +/−75 micrometers for example. In addition to a non-planar EM bottom surface, the LGA interconnect may not have sufficient compressive compliancy to absorb the effects of surface irregularities and structural deflections with the clamping techniques employed. Increasing the global clamping force may not be an option due to the increase in stress that the substrate of the EM may encounter, thereby possibly resulting in reduced life expectancy of the EM. Accordingly, it would be advantageous to have a method and apparatus for providing positive contact force in an EM assembly, as well as other face-to-face contact assemblies, without incurring undue component stress.